The best part of nd5 was that it made my life easier by providing all tools needed to discover devices in our environment at once! It's also pretty good when you need some help with configuration as there are many tutorials posted online which helps me understand things better or do them myself (it would be nice if this option could have been available more often).
Some features from NDS such us AD integration might not work properly unless they're configured correctly beforehand but I'm sure these can easily get resolved since ND 5 supports other platforms than Windows so no worries here either :) You don't really NEED any additional software apart form your existing infrastructure tooling like Tivoli/IBM App control - just try out what works well first before adding anything else onto top because sometimes those "more" extra components make problems worse instead solving issues ;).